Hello. I made a post about this a while back with the exact same issue. Its recently gotten worse, I've put it to sleep and after a bit, it just beeps, three times. I have a 128GB Samsung SSD, 6GB of RAM, and the 2.4GHz i5. It does the same thing in Lion, Mountain Lion, Mavericks, Yosemite, and El Capitan. My memory is good, according to memtest. I am at my wits end, I really don't want to have to fall back to my 2008.